SUMMARY:A process for dehydrating fish under vacuum and in contact with heated plates is described. Although the conditions, in respect of time and temperature, appeared suitable for microbial development, a reduction in the number of bacteria usually occurred. A survey of the data accumulated over twenty months, including a series of experimental production periods, showed that the bacterial population estimated at 22° was reduced in the process as a whole to about 1% of its initial value and that estimated at 37° to about 10%. Species of the genusMicrococcustended to predominate on the finished product. Contrary to earlier expectations, there should be no serious microbiological hazards if high standards of personal and factory hygiene are maintaine